WPT details: We have coverage for all basic uses of the API, including exception and error states, which should ensure a base-level uniformity across browser implementation of the API surface. Some deeper aspects of the API's implementation, such as which codecs are supported, vary from browser to browser and hence may not need to be tested by WPTs. Test status can be found at: https://wpt.fyi/results/webcodecs?label=master&label=experimental&aligned&q=webcodecs
Provides efficient, low-level access to built-in (software and hardware) media encoders and decoders.
Existing media APIs (HTMLMediaElement, Media Source Extensions, WebAudio, MediaRecorder, WebRTC) are high-level and narrowly-focused. A low-level codec API will better support emerging applications, such as latency-sensitive game streaming, client-side effects or transcoding, and polyfillable media container support, without the increased network and CPU cost of JavaScript or WebAssembly codec implementations.
Docs: https://github.com/WICG/web-codecs/blob/master/explainer.md
Explainers: https://github.com/WICG/web-codecs/blob/master/explainer.md